Update the passthrough command decoder to use the new CHROMIUM_copy_texture.

ui/gl/gl_stub_autogen_gl.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // This file is auto-generated from
 // ui/gl/generate_bindings.py
 // It's formatted by clang-format using chromium coding style:
 //    clang-format -i -style=chromium filename
 // DO NOT EDIT!
 
@@ skipping 153 matching lines @@
                                  GLsizei depth,
                                  GLenum format,
                                  GLsizei imageSize,
                                  const void* data) override {}
 void glCopyBufferSubDataFn(GLenum readTarget,
                            GLenum writeTarget,
                            GLintptr readOffset,
                            GLintptr writeOffset,
                            GLsizeiptr size) override {}
 void glCopySubTextureCHROMIUMFn(GLuint sourceId,
+                                GLint sourceLevel,
+                                GLenum destTarget,
                                 GLuint destId,
+                                GLint destLevel,
                                 GLint xoffset,
                                 GLint yoffset,
                                 GLint x,
                                 GLint y,
                                 GLsizei width,
                                 GLsizei height,
                                 GLboolean unpackFlipY,
                                 GLboolean unpackPremultiplyAlpha,
                                 GLboolean unpackUnmultiplyAlpha) override {}
 void glCopyTexImage2DFn(GLenum target,
@@ skipping 15 matching lines @@
 void glCopyTexSubImage3DFn(GLenum target,
                            GLint level,
                            GLint xoffset,
                            GLint yoffset,
                            GLint zoffset,
                            GLint x,
                            GLint y,
                            GLsizei width,
                            GLsizei height) override {}
 void glCopyTextureCHROMIUMFn(GLuint sourceId,
+                             GLint sourceLevel,
+                             GLenum destTarget,
                              GLuint destId,
+                             GLint destLevel,
                              GLint internalFormat,
                              GLenum destType,
                              GLboolean unpackFlipY,
                              GLboolean unpackPremultiplyAlpha,
                              GLboolean unpackUnmultiplyAlpha) override {}
 void glCoverageModulationNVFn(GLenum components) override {}
 void glCoverFillPathInstancedNVFn(GLsizei numPaths,
                                   GLenum pathNameType,
                                   const void* paths,
                                   GLuint pathBase,
@@ skipping 1014 matching lines @@
                               GLsizei stride,
                               const void* ptr) override {}
 void glVertexAttribPointerFn(GLuint indx,
                              GLint size,
                              GLenum type,
                              GLboolean normalized,
                              GLsizei stride,
                              const void* ptr) override {}
 void glViewportFn(GLint x, GLint y, GLsizei width, GLsizei height) override {}
 GLenum glWaitSyncFn(GLsync sync, GLbitfield flags, GLuint64 timeout) override;